Mapping of the alpha-actinin binding site within the beta 1 integrin cytoplasmic domain.
Mapping of the alpha-actinin binding site within the beta 1 integrin cytoplasmic domain.
复制标题
DOI：
10.1016/s0021-9258(19)36909-1
复制
发表时间：
1993-10
期刊：
影响因子：
--
通讯作者：
C. Otey;G. Vásquez;K. Burridge;B. W. Erickson
中科院分区：
文献类型：
--
作者：
C. Otey;G. Vásquez;K. Burridge;B. W. Erickson
肌动蛋白交联蛋白α-辅肌动蛋白与整联蛋白β 1亚基的胞质结构域结合，表明α-辅肌动蛋白可能在肌动蛋白细胞骨架和跨膜纤连蛋白受体之间形成直接连接。在这项研究中，我们已经使用短的合成肽本地化的β 1整合素的胞质结构域内的α-辅肌动蛋白的结合位点。四个13残基的肽进行了测试，在亲和色谱测定和固相结合测定。结果表明，两个区域的序列有助于α-辅肌动蛋白的结合：一个接近β 1胞质尾出现从膜和第二段位于胞质尾的C末端附近。使用模拟表位测定的改编更详细地研究了这种结合模式，其中来自β 1胞质结构域的32个重叠的连续十肽片段中的每一个都组装在不同塑料针的头部上。肽-钉结构用于检测125 I-α-辅肌动蛋白的结合。正如我们最初的结果所预测的那样，发现α-辅肌动蛋白与两个不同的肽段簇结合。这代表了一种新的使用模拟表位引脚分析映射结构蛋白的相互作用位点。
The actin cross-linking protein alpha-actinin binds to the cytoplasmic domain of the beta 1 subunit of integrin, suggesting that alpha-actinin may form a direct link between the actin cytoskeleton and the transmembrane fibronectin receptor. In this study, we have used short synthetic peptides to localize the binding site for alpha-actinin within the cytoplasmic domain of beta 1 integrin. Four 13-residue peptides were tested in both an affinity chromatographic assay and a solid-phase binding assay. The results indicated that two regions of sequence contribute to the binding of alpha-actinin: one near where the beta 1 cytoplasmic tail emerges from the membrane and a second segment located near the C terminus of the cytoplasmic tail. This binding pattern was investigated in more detail using an adaptation of the mimotope assay, in which each of the 32 overlapping sequential decapeptide segments from the beta 1 cytoplasmic domain was assembled on the head of a different plastic pin. The peptide-pin constructs were used to detect the binding of 125I-alpha-actinin. As predicted from our initial results, alpha-actinin was found to bind to two distinct clusters of peptide segments. This represents a novel use of the mimotope pin assay to map interactive sites on structural proteins.